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Installing Pavers Over Concrete

Many people wonder if they can lay pavers over an existing concrete patio or pad. The answer is, yes you can, provided that the conditions are right.  Here are a few critical things to keep in mind:

Condition of Existing Concrete: Any concrete slab that will be overlaid with pavers must be structurally sound with no evidence of cracking or deterioration.

Slope: The existing concrete pad must slope away (min 1” of fall for 8 feet of run) from any structures to ensure drainage.

Installation: The most important tip, you must create a drainage layer (1” of bedding sand) below the pavers. In doing so you allow for any water to drain away from pavers and off of the concrete slab (remember, the thinner the bedding layer, the greater risk of damaging the pavers). This drainage layer of coarse sand must also be retained by some form of border around the perimeter so that it doesn’t wash away over time. Once the pavers are installed and carefully compacted, and the joints are all straightened (adjust crooked lines with a screwdriver or small pry bar), fill the paver joints as you would on any other regular paver installation. Since your pavers are over concrete we recommend that you use a non-pervious polymeric sand to fill the joints.

Note: Keep in mind the height the paver will add to the concrete slab once installed. Most pavers are 2-3” (5-8cm) in height, plus your drainage layer. You must ensure this still lines up with adjoining building access (I.e. patio doors) and maintains proper step heights.

Adhering border pavers: It is a common practice to mortar or glue the perimeter pavers. We recommend that you always use concrete adhesive when gluing pavers to the perimeter of a concrete slab. It is stronger and easier to apply.

Below is a diagram to help better illustrate installing your pavers on top of a concrete base.

Caution: A bedding course of “clear chip” stone on a concrete pad will provide the necessary drainage required, but will provide little or no “give” when final compaction of the pavers is attempted. A best practice is to NOT compact the surface of the pavers as is the practice in a standard base installation.